1. What is Body Surface Area (BSA)?

Definition: BSA is the calculated surface area of a human body, often used in medical practice for drug dosage calculations and physiological measurements.

Purpose: It provides a more accurate measurement than body weight alone for determining proper medication dosages, especially for chemotherapy, pediatric doses, and other critical medications.

2. How Does the Calculator Work?

The calculator uses the Mosteller formula:

Where:

• \( BSA \) — Body Surface Area (square meters)
• \( W \) — Weight (kilograms)
• \( H \) — Height (centimeters)

Explanation: The formula calculates the approximate body surface area based on the geometric relationship between weight and height.

3. Importance of BSA Calculation

Details: BSA is crucial in medicine for:

• Determining correct drug dosages
• Calculating chemotherapy doses
• Assessing burn victims
• Pediatric medicine calculations
• Cardiac index measurements

4. Using the Calculator

Tips: Enter the patient's weight in kilograms and height in centimeters. Both values must be greater than 0.

5. Frequently Asked Questions (FAQ)

Q1: Why use BSA instead of weight for dosing?
A: BSA correlates better with metabolic processes and drug distribution than weight alone, especially for medications that don't distribute evenly in fatty tissue.

Q2: What's a normal BSA range?
A: Average BSA is about 1.7 m² for adult men and 1.6 m² for adult women, but varies significantly with body size.

Q3: Are there other BSA formulas?
A: Yes, including DuBois, Haycock, and Gehan-George formulas, but Mosteller is most common due to its simplicity and accuracy.

Q4: How accurate is BSA calculation?
A: It's an estimation - actual body surface varies with body composition, but provides a clinically useful approximation.

Q5: When is BSA not appropriate for dosing?
A: For drugs primarily distributed in fatty tissue or when dosing based on therapeutic drug monitoring.